Carburetor spray nozzle



Oct. 1, 1929. G. TRIBBETT CARBURETOR SPRAY NOZZLE NEY Patented @et l, 1929 Win09@ CARBURETOB. SPRAY NOZZLE i Application led March 23, 1926.

This invention relates to a spray nozzle for use in carburetors and the like and the primary object is the provision of a. nozzle Which Will be very simple in construction, which Will be extremely efficient and operate to give a very satisfactory dispersion and even flow of fuel.

A further object of the invention is the provision of a spray nozzle Which is provided With an in erior passage having a single point of restriction intermediate its ends, this passage dii/'erging frusto-conically and similarly to each end, so as to provide a gradually tapering enit passage from the point of resniction, in Which the fuel may expand and be completely atomized before it is acted upon or comes in Contact with the air surrounding the exit. The passage is entirely unrestricted for the flow of fuel and it is devoid' of bleeder openings so that the fuel may have the proper lioiv at the restricted portion of the passage to provide for complete dispersion and atomization.

Further objects and advantages of my invention will be more fully set forthy in the attached specification and by reference to the accompanying drawings in Which section -Referring more particularly to thc draw- Y ing by reference numerals, the fuel spray nozzle indicated generallv b the numeral 1 isV shown mounted in the Venturi-shaped passage 2 of the carburetor 3 which is supplied vvith air intake passage 1, throttle valve 5, float chamber 6 and fuel supply passage 7, leading from the float chamber to the space 8 below the entrance of the nozzle 1. rEhe loiver part of this space S is closed by a plug 9 which may be removed to permit the removal of the nozzle 1 which is screwed into the carburetor from beloiv.

rEhe nozzle 1 has its enit 1() in the region of the restricted portion of the Venturi-shaped passage 2 and has its intake opening 11 projecting into the fuel space S. The nozzle is a circular tube having the external threads 12,

Serial No. 96,837.

flange 13 and the slotted end 14 adapted for engagement by a screw driver and by means Y of which the nozzle may be mounted in position. i

rThe interior passage of the nozzle is of novel construction, so designed as to give maximum dispersion of the fuel and entire mixture with the air to provide an explosive mixture of gasoline and air When used for a supply of fuel to an internal combustion engine. The internal passage designated generally 15 has t-Wo frusto-conical inlet and outlet passages 17 and 16 which gradually converge in a similar manner from the ends of the tube or nozzle 1 and Which form substantially midway of the nozzle a knife edge restriction Which breaks up the continuity of the flow forming small eddies giving the effect of a line spray rather than continuous flow of fluid. lillhe taper in the tivo passages 17 and 18 is preferably exactly the same, and the inlet and exit openings are entirely unrestricted to the How of fuel therethru.

Under the conditions as just `4outlined, it has been found that gasoline will be very finely divided and dispersed when it is sucked out of the ,exit opening by the suction createdl in Fig. 1 is a transverse section through the carburetor, showing the manner in which the i the internal combustion engine and by the rapid flow of air past the exit 10. The intake opening 11 extending unrestrictedly into the space 8 beneath it, allows a steady convergence of the flow of the fuel through the passage 17 so that when it reaches-the restricted portion 16 it has an exceedingly high speed and a regular flow up to this point. vAt this point, however, the various particles of the gasoline are permitted to immediately and instantaneously start expanding, and the result has been found to be that the gasoline continues its flow through the passage 18 in the form' of a hollow cone travelling along the sides of the passage. By the time the fuel has reached the eXit opening 10, it is very fine-` ly divided and occupies a vcross-sectional area far in excess of the area at the restriction 16. Itis permitted to so expand and divide and disperse itself up to the eXit opening 10, since it is protected in doing so .by the side Walls of the passage 18, Which prevent interference in thisaction upl to the exit opening l() from the rapidly flowing air outside of the nozzle. At the exit 10 the fuel emerges from the nozzle and continues to expand, but at the same time it comes in contact with the rapidly flowing air around it, and due to its great dispersion and atomization, it is thoroughly mixed with the air and absorbed thereby to form a very satisfactory explosive mixture.

The length of the nozzle is preferably at least several times the diameter of the exit opening, and the taper on the contracting and expanding inlet and outlet passages of the nozzle is preferably a slight taper, as shown on the drawing. The size of the restricted point 16 of the passage varies with the different shapes and sizes of Venturi air passages in which it is used and varies with the size of engine it is to supply. The restriction 16 is made of such size that with the engine supplied developing power, a proper fuel mixture willbe supplied through the carburetor. It has been found that if the restriction 16 will properly supply the fuel mixture under such a condition, it will also supply the proper mixture at idling and at all other conditions normally obtained in the running of the engine. It has been found that it is unnecessary to supply compensating means for increasing or decreasing the richness ,of the mixture under various conditions. It has also been found that the carburetor will not function in the manner desired and will not provide a proper dispersion of the fuel if the exit opening 10 is in any way restricted, or if the passage through the carburetor is provided with bleeder openings for the entrance of either air or gasoline.

Under the conditions as set forth in accordance with my preferred form of invention it has been found that the dispersion or expansion of the fuel after it leaves the exit opening 10 of the nozzle continues on in a frustoconical formation, this expansion and dispersion taking place for a considerable distance after the fuel has left the nozzle.

I am aware that various changes may be made in the construction which has been outlined for purposes of illustration of my invention Without departing from the spirit or scope thereof and do not intend to be limited to the precise form of construction herein set forth.

I claim A metering nozzle comprising a tube having a substantially knife edge restriction in its interior intermediate of its end and frustoconical inlet and outlet passages flaringout- Wardly from either end of said restriction, the length Vof the outlet passage being greater than the diameter of its exit opening and the wall of the nozzle being imperforate.

In testimony whereof I afx my signature.

GEORGE TRIBBETT.- 

